Fluid heating and discharging device



April 10, 1945;-

R. MEIKLEJOHN, JR

FLUID HEATING AND DISCHARGING DEVICE Filed Sept. 17, 1942 INVENTOR ROBERT MEIKLEJOHNJR.

ATTORNEY Patented Apr. 10, 1945 Robert Meiklejolin, Jr; Westiield. N. 1., asllgnor to Union Carbide and Carbon Corporation, a corporation of New York Application fleptember 17, 1942, Serial No. 458,701

mi. 2s 11o) tional blowpipe with a fluid heating and dis- ...charging device embodying my invention at- 13 Claims.

This invention relates generally to a fluid heating and discharging device. and relates particulariy to a readily attachable and detachable fluid heating, and discharging unit for use with a conventional torch, such as an acetylene torch or blowpipe, and adapted to discharge a jet of heated Y compressed .air, or alternatively other fluid under pressure. to a selected area or work surface.

It frequently becomes necessary to direct jets of moderately heated fluids-against bodies to heat or warm the same to a desired extent. For example, a moderately heated air jet may be directed against a surface to dry it rapidly, or against a thermoplastic body to render it ductile. Specifically, it is customary towarm vinyl resin strips to allow them to be bent to desired shapes. Such strips flnd extensive use as mechanical templets for shape cutting machines and other types of reproducing apparatus.

Also, because of the inflammable, nature of many materials against which such heating jets are applied, it is important that proper provision be made in such heating devices to safeguard against fire hazards occurring when the heated surface is not properly shielded from an open flame, or where the heated fluid is not maintained within safe temperature limits.

Among the objects of this invention are: to provide a fluid heating and discharging device capable of discharging a jet of indirectly heated air, gas, or other fluid, against a work surface while shielding the work surface from the heating flame; to provide a compact fluid heating and discharging device adapted to be readily attached to, or detached from, a conventional torch or blowpipe, and to provide means cooperative with such a device to control the flow of fluids therethrough; to provide such a fluid heating and distached thereto;

Fig. 2 is an enlarged longitudinal sectional view through the coil assembly shown in Fig. 1; Fig. 3 is a bottom plan view of the coil assembly I as seen from the line 3-3 of Fig. 2'; and

passage provided with an inlet and an outlet; a,

fluid conduit which is connected to a source of fluid under pressure, and which is closely coiled around the major part of the nozzle but spaced therefrom soas to provide a chamber. therebetween into which the flame of the torch may be projected to heat both the conduit and the nozzle, and the fluid therein; and means constituting a barrier between the front portion of the conduit order to prevent the flame from contacting the work, while providing ample flow of air into the chamber for supporting combustion of the flame. These and other objects will become apparent from the following description and from the accompanying drawing disclosing one form of the present invention which is not to be deemed limitative thereof. In the drawing:

Fig. 1 is a side elevational view of a convenin comparison with its diameter and is formed of and the nozzle to prevent any flame, from impinging against the workpiece.

The invention may utilize any desired type of torch or blowpipe B comprising a handle ill, a flame adjusting valve l I, and a nozzle or stem i2. Any conventional type of combustible gas or gaseous mixture may be used to provide a high temperature heating flame. Although a small oxy-acetylene flame may be utilized, satisfactory results may be obtained with a flame formed of a burning mixture of air and a combustible gas, such as acetylene. The particular blowpipe B illustrated is of the acetylene type and includes a combustible gas or acetylene inlet i3; thefflo w of which is regulated by the adjustable gvalve II. A mixer it at the forward end of the blowpipe handle communicates with an air inlet i5 and provides admixture between the air and the combustible gas, thereby forming a mixture that is discharged from a blowpipe tip it at the forward end of the stem 12, to produce a heating flame when such discharging mixture is ignited.

A heating'and discharging element H is removably attached to the blowpipe B and will normally be located directly adjacent tip vIii so that the flame is directed interiorly of element H. Element H preferably comprises a cylinder consisting of a helically wound coil or conduit ilof thermally conductive-tubing, which will usually be formed of brass. The coil ll preferably is long closely wound and directly contacting turns so as to form a relatively continuous cylindrical outer wall for a flame chamber l8. However, normally at least some of the turns adjacent to the midsection' of the coil are spaced slightly to provide annular passages IQ for the admission of air into the chamber l8 within the coil to aid completion of combustion.

Ordinarily, an inlet tube 2| connects with the front end of the coil IT and extends longitudinally of the coil I'l toward the tip l8 and thence continues along the stem l2 and handle ill for connection with an inlet fitting 22 at the rear of the blowpipe. As illustrated, the inlet fitting 22 comprises an inlet connection 23 communieating with a source of compressed air, although other fluids either liquid or gaseous in nature may be heated if desired. The flow of fluid through both the tube 2! and the coil I1 is regulated by an adjustable fluid control valve indicated at 24. The entire heating element assembly may be attached to the blowpipe B in any suitable manner, for example, by front and rear clamps 25 and 26.

Coil I! has an outlet gooseneck 21 discharging into agenerally conical nozzle N having a flared discharge outlet 29 and extending substantially axially through the coil [1. The small or rear end 30 of the nozzle N is hard soldered or otherwise secured to the coil outlet gooseneck 21. The wall of nozzle N constitutes the inner wall of flame chamber 18, and the heated fluid from gooseneck 21 is further heated while flowing through the flame-heated nozzle N and then is discharged from the nozzle outlet 29. The large diameter end of nozzle N includes an exterior annular flange or collar 3| which engages the inner surface of the coil I! at its front end, and not only aids heat exchange but closes the front end of chamber I8 and thereby shields and screens the work from the direct flame from the tip it. It will be observed that flange 3| preferably frictionally engages a plurality of the adjacent turns of the coil I'I thereby providing alignment between the coil I! and the nozzle N and also acts as a barrier to shield the work from the flame. By flaring the outlet 29 of nozzle N a relatively large volume of air or other fluid may beprojected from the heating element at relatively low velocity, and it will be recognized that varying the inlet valves II and 24 to adjust the flows of the combustible gas and the compressed air permits an adjustment of the temperature of the discharging air over a considerable range.

The clamp 25 preferably comprises a pair of plates 32 and 33 held together in any convenient manner as by a single machine screw 34. The plates 32 and 33 are grooved to accommodate the tip IS, the inlet tube 2|, and the small diameter end or rear portion 30 of the nozzle N, thereby holding all parts rigidly in a preferred predetermined relation. The grooves in the plates 32 and 33 are parallel so that the flared outlet 23 of nozzle N will extend in substantially the same direction' as the tip 15. C1amp'28 normally will be similarly arranged as clamp 25 and will be provided with single screw 35 to clamp gas and air inlets l3 and 23 in preferably fixed parallel relation.

By this construction and arrangement of parts it will be observed that I provide a readily attachable and detachable fluid heating and discharging device for use with a conventional acetylene torch, an oxy-acetylene blowpipe or like heating means, which is capable of heating a varying flow of compressed air, or other fluid, to

a readily adjustable extent, and that all flame is shielded from the work.

The preferred embodiment of my invention described above is illustrative only and it will be recognized that various changes may be made in the construction and arrangement here disclosed without departing from the principles of the invention or sacrificing its advantages.

What is claimed is:

1. A fluid heating and discharging device comprising, in combination, a fluid discharging nozzle having a longitudinal fluid passage provided with an inlet and an outlet; a fluid conduit having an inlet and also having an outlet connected to the nozzle inlet; said conduit surrounding the major part of said nozzle but having at least a portion thereof spaced from said nozzle to provide a chamber between said conduit and said nozzle to receive the heating flame from a blowpipe or the like, to heat both said conduit and said nozzle and the fluid flowing therethrough; and means providing a barrier between front portions of said conduit and said nozzle, to close the front end of said chamber and thereby prevent such flame from impinging against a workpiece heated by the fluid discharging from said nozzle.

2. In combination, a blowpipe and a fluid heating and discharging device comprising a fluid discharging nozzle having a longitudinal fluid passage provided with an inlet and an outlet; a fluid conduit having an inlet and also having an outlet connected to the nozzle inlet; said conduit surrounding the major part of said nozzle but having at least a portion thereof spaced from said nozzle to provide a chamber between said conduit and said nozzle to receive the heating flame from said blowpipe, to heat both said conduit and said nozzle and the fluid flowing therethrough; and a means providing a barrier between front portions of said conduit and said nozzle, to close the front end of said chamber and thereby prevent such flame from impinging against a workpiece heated by the fluid discharging from said nozzle.

3. A fluid heating and discharging device comprising, in combination, a fluid conduit constructed and arranged to surround a chamber adapted to receive a heating mediumfor heating said conduit; and fluid discharging means communicating with and surrounded by said conduit and also adapted to be heated by said heating medium.

4. A fluid heating and discharging device as claimed in claim 3, wherein said conduit comprises helically wound tubing having a fluid inlet adjacent the outlet of said fluid discharging means.

5. A fluid heating and discharging device attachable to a blowpipe, said device comprising, in combination, a fluid conduit constructed and arranged to surround a chamber adapted to receive a flame from said blowpipe for heating said conduit; fluid discharging means communicating with and surrounded by said conduit and also adapted to be heated by said flame; and means to inhibit impingement of said flame against the work onto which such heated fluid is discharged.

6. A fluid heating and discharging device as claimed inclaim 5, wherein said conduit comprises helically wound tubing having at least one turn thereof spaced from an adjoining turn to provide a passage for admitting. air into said flame.

7. A fluid heating and discharging device as claimed in claim 5, wherein said conduit has a fluid inlet adjacent the outlet of said fluid discharging means, said conduit and said fluid discharging means having portions cooperating to prevent impingement of said flame against the work onto which such heated fluid is discharged.

8. A fluid heating and discharging device adapted to heat and discharge a stream of heated fluid against a selected work surface, which comprises a hollow heat exchange mean through which the fluid flows and adapted to be heated by a flame, said heat exchange meanshaving a fluid inlet and a fluid .outlet and enclosing a chamber into which the flame is adapted tobe projected; and shielding means associated with said heat exchange means for shielding the work from direct contact with said flame, said heat exchange means including heat conductive tubing and said shielding means comprising an elongated member within said chamber, said member having an axial passage connected'to the outlet of said heat exchange means and through which the fluid is discharged.

9. A fluid heating and discharging device adapted to heat and discharge a stream of heated fluid against a selected work surface, which comprises a hollow heat exchange means through which the fluid flows and adapted to be heated by a flame, said heat exchange means having a fluid inlet and a fluid outlet and enclosing a chamber into which a flame is adapted to be projected; and shielding means associated with said heat exchange means ior shielding the work from direct contact with said flame, said heat exchange means including heat conductive tubing and said shielding means comprising a flanged generally conicaladapted to be heated by a flame, said cylinder having a fluid inlet and a fluid outlet and encloscontact with a flame, said shielding means com prising an elongated member fitted within said chamber and having an axial passage therethrough to discharge compressed air, said axial passage having a flared discharge opening and being connected to the outlet of said cylinder; and clamping means for clamping said device to a blowpipe.

12. A fluid heating and discharging device adapted to discharge a stream of heated compressed air against a selected work surface, which device comprises, a hollow cylinder formed of closely adjacent turnsof heat conductive tubing adapted to be'heated by a flame, said cylinder having a fluid'inlet and a fluid outlet and enclosing a chamber adapted'to receive a flame, and

certain of said turns of tubing substantially in the mid-section of said cylinder being spaced apart to provide restricted air spaces, the remaining turns of tubing being directly adjacent one to another; shielding means associated with said cylinder for shielding the work from direct content with a flame, said shielding means comprising a generally conical shaped member disposed within said chamber with the narrow top part of the conical member disposed at the rear of said cylinder and with the base of the conical shaped member disposed at the front end of the cylinder. said conical shaped member being provided with an axial passage running therethrough. and a flange integral with said conical shaped member located at the base thereof and in frictional contact with the front end of said cylinder so as to form a shield between a flame within said chamber and the work; and clamping means for clamping said device toa blowpipe.

13. A fluid heating and discharging device 'adapted to discharge a stream of heated compressed air against a selected work surface, which so device comprises, a hollow cylinder formed of ing a chamber adapted to receive a flame, and

said turns of tubing being spaced one from another intermediate the ends of said cylinder'to provide for the admission of air to said chamber, the remaining turns of tubing being in contact one with another; shielding means disposed with-""" in said cylinder for shielding the work from direct contact with a flame; and clamping means for clamping said device to a blowpipe.

11. A fluid heating and discharging device vadapted to discharge a stream of heated compressed air against a selected work surface, which device comprises a hollow cylinder formed of closely adjacent turns of heat conductive tubing closely adjacent turns 0! heat conductive tubing adapted to be heated by a flame, said cylinder having a fluid inlet and a fluid outlet and enclosing a chamber adapted to receive a flame and certain of said turns of tubing substantially in the ,mid-section of said cylinder being spaced apart to provide restricted air spaces, the remaining'turns of tubing being directly adjacent one to another; shielding mean associated with said cylinder for shielding the work from direct contact with a flame, said shielding means comprising a generally conical shaped memberdisposed within said chamber with the narrow top part of the conical member disposed at the rear of said cylinder and with the base of the conical shaped member disposed at the front end of the cylinder, said conical shaped member being provided with an axial passage running therethrough 303mm: an. 

